“It started with me stalking a nun with a cashmere goat farm,” said Melissa Ventosa Martin, the founder of Old Stone Trade, an online marketplace for wares made by international artisans.

Since 2021 Ms. Ventosa Martin, 45, has peddled made-to-order items like a green tweed kilt from Andrea Chappell’s Acme Atelier in Scotland or hand-stitched loafers from Aldanondo y Fdez in Spain — the kinds of rare, high-quality things she once bought while traveling in her former career as a fashion editor.

Two years ago she began planning a collection around the concept of a “classic” American uniform: jeans, a perfect cashmere sweater, an oversized blazer, a leather bag with the same level of finish and luster you might find at Hermès.

The challenge was finding people capable of producing luxury items at a small scale, which is why she eventually tracked down the nuns and their goats at the Adirondack Wool Festival. They, in turn, introduced her to Clean Cashmere, a company that works with small American farms. “They help them source and clean and spin their wool,” Ms. Ventosa Martin said.

The result is a three-quarter sleeve, ribbed henley sweater by Maggie Koluch, a knitter based in New York, using undyed cashmere, scoured and spun in the U.S.

Each piece in the collection tends to have a similarly labyrinthine story — exactly the kind of storytelling Ms. Ventosa Martin wanted for her small company.

“Handmade in America” also includes a blue jean and a jacket made by Glenn Liburd of Glenn’s Denim for Old Stone Trade, who is based in Providence, R.I., and once led the custom program for Levi’s.

“It doesn’t get more American than jeans,” said Mr. Liburd, 68, who grew up in Trinidad and Tobago. “Soldiers were wearing denim fabrics to go to battle and then it trickled down to work wear and cowboys and it just kept trickling down to what we know it as today.”

He created a ’90s style jean, (with a rise somewhere between high and mid, and a straight leg) from dead-stock organic selvidge denim, woven on original shuttle looms in Greensboro, N.C. Each pair is hand embroidered and numbered, with a limited edition of 10 in the first drop. The jeans, like all the products at Old Stone Trade, are made to order.

“There are a few measurements that we take and then a spot for the client to put in notes if they like them to fit a certain way,” Ms. Ventosa Martin said. In addition to the collaborations, she designed a day-dress inspired by 1930s nurse uniforms. And an oversized navy wool blazer inspired by a photo of David Letterman from the 1990s will be made by Greenfield Clothiers in Brooklyn, along with white wool trousers.

All of this commitment to craftsmanship, though, comes at a price. On the high end, an olive calfskin bag made entirely by hand from Lili Storella Leather in New Hampshire will retail for $6,200. (Ms. Ventosa Martin notes that Ms. Storella’s handbags, from her store Mila.jito, typically have a six-month waiting list.)

“We’re trying to help the customer understand why things cost what they do,” Ms. Ventosa Martin said, when asked if potential customers ever push back or complain about the prices. “These artisans are getting paid for their time and work and their craft and our margins as a retailer are not huge. The whole point is really that they’re getting paid what they should be getting paid.”

In addition to word of mouth, Ms. Ventosa Martin often finds collaborators on social media. The Cowichan Sweater, a shawl collar cardigan, comes from the Knit With Purpose collective in British Columbia, Canada, each made by indigenous Coast Salish knitters. “She reached out and we got the knitters together who were excited at the idea of collaborating,” said Ron Rice, the executive director of Knit With Purpose.

Ms. Ventosa Martin is including Canada as part of the American collection. “We have always talked about the fact that lines on a map mean different things to different people,” Mr. Rice said. “The lines for indigenous people are arbitrary, they span both Canada and the United States.”

She added: “This is a great moment to highlight American craft. There’s so much talent and it’s very diverse. Everything is done here and it’s really meaningful to see that process.”